P0037
2GR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0037, P0038, P0057, P0058, P0141, P0161: Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)
P0161 - Oxygen Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
DESCRIPTION
Refer to DTC P0136 P0136.
HINT
- When any of these DTCs are set, the ECM enters fail-safe mode. The ECM turns off the Heated Oxygen (HO2) sensor heater in fail-safe mode. Fail-safe mode continues until the engine switch is turned off.
- The HO2 sensor heater circuit uses a relay on the +B side of the circuit.
MONITOR DESCRIPTION
The sensing portion of the Heated Oxygen (HO2) sensor has a zirconia element which is used to detect the oxygen concentration in the exhaust gas. If the zirconia element is at the appropriate temperature, and the difference between the oxygen concentrations surrounding the inside and outside surfaces of the sensor is large, the zirconia element generates voltage signals. In order to increase the oxygen concentration detecting capacity of the zirconia element, the ECM supplements the heat from the exhaust with heat from a heating element inside the sensor.
Heated oxygen sensor heater range check (P0037, P0038, P0057 and P0058):
The ECM monitors the current applied to the HO2 sensor heater to check the heater for malfunctions. If the current is below the threshold value, the ECM will determine that there is an open circuit in the heater. If the current is above the threshold value, the ECM will determine that there is a short circuit in the heater.
Example:
The ECM sets DTC P0038 or P0058 when the current in the HO2 sensor heater is more than 2 A. Conversely, when the heater current is less than 0.3 A, DTC P0037 or P0057 is set.
Heated oxygen sensor heater performance (P0141 and P0161):
After the accumulated heater on time exceeds 100 seconds, the ECM calculates the heater resistance using the battery voltage and the current applied to the heater. If the resistance is above the threshold value, the ECM will determine that there is a malfunction in the HO2S heater and set DTC P0141 and P0161.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All:
P0037 and P0057:
P0038 and P0058 (Case 1):
P0038 and P0058 (Case 2):
P0038 and P0058 (Case 3):
P0141 and P0161:
TYPICAL MALFUNCTION THRESHOLDS
P0037 and P0057:
P0038 and P0058 (Case 1 and 2):
P0038 and P0058 (Case 3):
P0141 and P0161 (Heater performance monitor check):
COMPONENT OPERATING RANGE
MONITOR RESULT
- Refer to Checking Monitor Status Mode 6 Data.
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the Techstream on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
4. Turn the engine switch off and wait for 30 seconds.
5. Turn the engine switch on (IG) and turn the Techstream on [A].
6. Start the engine and idle it for 5 minutes or more [B].
7. With the vehicle stationary, depress the accelerator pedal and maintain an engine speed of 3000 rpm for 1 minute [C].
8. Idle the engine for 5 minutes or more [D].
9. Enter the following menus: Powertrain / Engine / Trouble Codes / Pending.
10. Read the pending DTC [E].
HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
11. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
12. Input the DTC: P0037, P0038, P0057, P0058, P0141 or P0161.
13. Check the DTC judgment result.
HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [B] through [D] again.
14. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
15. Check the DTC judgment result.
HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
16. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
Refer to DTC P0136 P0136.
INSPECTION PROCEDURE
HINT
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction Freeze Frame Data.
- Bank 1 refers to the bank that includes the No. 1 cylinder*.
*: The No. 1 cylinder is the cylinder which is farthest from the transmission.
- Bank 2 refers to the bank that does not include the No. 1 cylinder.
- Sensor 1 refers to the sensor closest to the engine assembly.
- Sensor 2 refers to the sensor farthest away from the engine assembly.
PROCEDURE
1. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
(a) Disconnect the K34*1, K57*2 or V35*3 heated oxygen (HO2) sensor connector.
HINT
- *1: Bank 1 Sensor 2
- *2: Bank 2 Sensor 2 (2WD)
- *3: Bank 2 Sensor 2 (4WD)
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance (Bank 1 Sensor 2):
Standard resistance (Bank 2 Sensor 2):
(c) Reconnect the HO2 sensor connector.
NG -- REPLACE HEATED OXYGEN SENSOR
OK -- Continue to next step.
2. CHECK TERMINAL VOLTAGE (+B OF HO2 SENSOR)
(a) Disconnect the K34*1, K57*2 or V35*3 HO2 sensor connector.
HINT
*1: Bank 1 sensor 2
*2: Bank 2 sensor 2 (2WD)
*3: Bank 2 sensor 2 (4WD)
(b) Turn the engine switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage (Bank 1 sensor 1):
Standard voltage (Bank 2 sensor 1):
(d) Reconnect the HO2 sensor connector.
NG -- INSPECT EFI NO. 2 FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)
(a) Check the harness and connector between the ECM and HO2 sensor.
(1) Disconnect the K34*1, K57*2 or V35*3 HO2 sensor connector.
HINT
*1: Bank 1 sensor 2
*2: Bank 2 sensor 2 (2WD)
*3: Bank 2 sensor 2 (4WD)
(2) Disconnect the A7 ECM connector.
(3) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):
Standard resistance (Check for short):
(4) Reconnect the HO2 sensor connector.
(5) Reconnect the ECM connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
4. INSPECT EFI NO. 2 FUSE
(a) Remove the EFI No. 2 fuse from the No. 2 engine room relay block.
(b) Measure the resistance of the EFI No. 2 fuse.
Standard resistance:
Below 1 Ohms
(c) Reinstall the EFI No. 2 fuse.
NG -- CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - EFI NO. 2 FUSE)
(a) Check the harness and connector between the HO2 sensor and EFI No. 2 fuse.
(1) Disconnect the K34*1, K57*2 or V35*3 HO2 sensor connector.
HINT
*1: Bank 1 sensor 2
*2: Bank 2 sensor 2 (2WD)
*3: Bank 2 sensor 2 (4WD)
(2) Remove the EFI No. 2 fuse from the No. 2 engine room relay block.
(3) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):
Standard resistance (Check for short):
(4) Reconnect the HO2 sensor connector.
(5) Reinstall the EFI No. 2 fuse.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - EFI NO. 2 FUSE)
(a) Remove the EFI No. 2 fuse from the No. 2 engine room relay block.
(b) Remove the integration relay from the No. 2 engine room junction block.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):
Standard resistance (Check for short):
(d) Reinstall the EFI No. 2 fuse.
(e) Reinstall the integration relay.
NG -- REPLACE ENGINE ROOM NO. 2 RELAY BLOCK, JUNCTION BLOCK
OK -- CHECK ECM POWER SOURCE CIRCUIT